Drill assembly for preparation of surgical sites

ABSTRACT

This disclosure relates to a drill assembly and method for preparing a surgical site. The drill assembly disclosed herein may be utilized for removing bone prior to positioning a graft and/or implant at a surgical site.

BACKGROUND

This disclosure relates to surgical devices and methods for preparingsurgical sites, such as forming recesses in bone.

Many bones of the human musculoskeletal system include articularsurfaces. The articular surfaces articulate relative to other bones tofacilitate different types and degrees of joint movement. The articularsurfaces can erode (i.e., experience bone loss) over time due torepeated use or wear or can fracture as a result of a traumatic impact.These types of bone defects can cause joint instability and pain.

Bone deficiencies may occur along the articular surfaces of the glenoidbone. Some techniques utilize a bone graft and/or implant to a filldefect in the glenoid bone. A drill may be utilized to form a recess inthe bone dimensioned to receive a portion of the implant.

SUMMARY

This disclosure relates to surgical devices and methods. The surgicaldevice may be used during methods for preparing surgical sites,including repairing bone defects. The surgical device described hereinmay be utilized to form a recess or otherwise shape a surface at asurgical site.

A drill assembly for preparation of a surgical site according to anembodiment of the present disclosure includes, inter alia, a drill shaftincluding one or more cutting surfaces, and a depth collar dimensionedto at least partially cover the one or more cutting surfaces. The depthcollar includes a first set of teeth, a ratcheting sleeve including asecond set of teeth, and, when the first set of teeth and the second setof teeth are engaged together, the ratcheting sleeve limits movement ofthe depth collar.

A drill assembly for preparation of a surgical site according to anembodiment of the present disclosure includes, inter alia, a drill shaftincluding one or more cutting surfaces, a depth collar movable along theone or more cutting surfaces in response to relative rotation betweenthe depth collar and the drill shaft, the depth collar including adistal end portion dimensioned to contact bone adjacent to the one ormore cutting surfaces, and a ratcheting sleeve moveable along the drillshaft between a first position and a second, different position relativeto a longitudinal axis of the drill shaft. The ratcheting sleeve isspaced apart from the depth collar in the first position and is engagedwith the depth collar in the second position such that the ratchetingsleeve limits relative rotation between the depth collar and the drillshaft.

A method of preparing a surgical site according to an embodiment of thepresent disclosure includes, inter alia, moving a depth collar relativeto a drill shaft such that the depth collar at least partially coversone or more cutting surfaces of the drill shaft, moving a ratchetingsleeve along the drill shaft to engage the depth collar such that theratcheting sleeve limits relative rotation between the depth collar andthe drill shaft, and rotating the drill shaft to remove tissue at asurgical site.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a perspective view of an exemplary drill assembly forpreparing a surgical site.

FIG. 2 illustrates a side view of the assembly of FIG. 1.

FIG. 3 illustrates a side view of a drill shaft.

FIG. 4 illustrates a sectional view taken along a length of the assemblyof FIG. 2.

FIG. 5 illustrates an exploded view of selected components of theassembly of FIG. 1.

FIG. 6 illustrates a side view of a ratcheting sleeve positionedrelative to the drill shaft of FIG. 3.

FIG. 7 illustrates a depth collar and a ratcheting sleeve according toanother embodiment.

FIG. 8 illustrates an exemplary method for preparing a surgical site.

FIG. 9 illustrates the instrument of FIG. 1 situated at a surgical site.

FIG. 10 illustrates the instrument of FIG. 1 situated at anotherposition relative to the surgical site of FIG. 9.

FIG. 11 schematically illustrates an implant and graft positioned at asurgical site.

FIG. 12 illustrates an isolated perspective view of the graft of FIG.11.

DETAILED DESCRIPTION

This disclosure relates to surgical devices and methods for preparing asurgical site, including repairing bone defects. The device describedherein may be capable of dimensioning or otherwise preparing a defectsurface at a surgical site, including removing bone or other tissue toform a hole or recess at a selected depth.

A drill assembly for preparation of a surgical site according to anembodiment of the present disclosure includes, inter alia, a drill shaftincluding one or more cutting surfaces, and a depth collar dimensionedto at least partially cover the one or more cutting surfaces. The depthcollar includes a first set of teeth, a ratcheting sleeve including asecond set of teeth, and, when the first set of teeth and the second setof teeth are engaged together, the ratcheting sleeve limits movement ofthe depth collar.

In a further embodiment, the drill shaft includes an intermediateportion between a shank portion and a drill body portion. The drill bodyportion includes the one or more cutting surfaces, the depth collarincludes first threading along a first passageway dimensioned to atleast partially receive the intermediate portion, and the intermediateportion includes second threading dimensioned to engage with the firstthreading such that relative rotation between the depth collar and theintermediate portion causes the depth collar to move along alongitudinal axis of the drill shaft.

In a further embodiment, the depth collar includes a first set of teeth,and the ratcheting sleeve includes a second set of teeth dimensioned tomate with the first set of teeth to oppose relative rotation between thedepth collar and the drill shaft.

In a further embodiment, the first set of teeth extend axially from aproximal end portion of the depth collar relative to the longitudinalaxis, and the second set of teeth extend axially from a distal endportion of the ratcheting sleeve relative to the longitudinal axis.

In a further embodiment, a spring member biases the second set of teethtowards the first set of teeth.

In a further embodiment, the depth collar includes a viewing window atleast partially axially aligned with the one or more cutting surfacesrelative to the longitudinal axis.

In a further embodiment, a spring member biases the ratcheting sleevetowards the depth collar in an installed position.

In a further embodiment, the drill shaft includes an intermediateportion between a shank portion and a drill body portion. The drill bodyportion comprising the one or more cutting surfaces. The intermediateportion includes a first shoulder. The ratcheting sleeve includes asecond passageway at least partially receiving the intermediate portion,and the ratchet sleeve includes a second shoulder along the secondpassageway. The spring member is compressible between the first shoulderand the second shoulder in response to moving the ratcheting sleeve in adirection away from the drill body portion.

In a further embodiment of any of the foregoing embodiments, theintermediate portion includes a slot, and a retention pin ismechanically attached to the ratcheting sleeve such that the retentionpin is at least partially received in the slot.

In a further embodiment, the retention pin extends inwardly from asidewall of the ratcheting sleeve bounding the second passageway suchthat the retention pin limits relative rotation between the ratchetingsleeve and the drill shaft.

In a further embodiment, the drill shaft includes a shaft passagewayextending along a longitudinal axis between the shank portion and thedrill body portion such that the shaft passageway intersects the slot.

A drill assembly for preparation of a surgical site according to anembodiment of the present disclosure includes, inter alia, a drill shaftincluding one or more cutting surfaces, a depth collar movable along theone or more cutting surfaces in response to relative rotation betweenthe depth collar and the drill shaft, the depth collar including adistal end portion dimensioned to contact bone adjacent to the one ormore cutting surfaces, and a ratcheting sleeve moveable along the drillshaft between a first position and a second, different position relativeto a longitudinal axis of the drill shaft. The ratcheting sleeve isspaced apart from the depth collar in the first position and is engagedwith the depth collar in the second position such that the ratchetingsleeve limits relative rotation between the depth collar and the drillshaft.

In a further embodiment, the depth collar includes a first set of teeth,and the ratcheting sleeve includes a second set of teeth dimensioned tomate with the first set of teeth in the second position.

In a further embodiment, a retention pin limits relative rotationbetween the ratcheting sleeve and the drill shaft.

A method of preparing a surgical site according to an embodiment of thepresent disclosure includes, inter alia, moving a depth collar relativeto a drill shaft such that the depth collar at least partially coversone or more cutting surfaces of the drill shaft, moving a ratchetingsleeve along the drill shaft to engage the depth collar such that theratcheting sleeve limits relative rotation between the depth collar andthe drill shaft, and rotating the drill shaft to remove tissue at asurgical site.

In a further embodiment, the step of moving the depth collar includesrotating the depth collar and drill shaft relative to each other suchthat first threading along the depth collar engages second threadingalong the drill shaft.

In a further embodiment, the step of moving the ratcheting sleeve alongthe drill shaft includes causing a first set of teeth along a proximalend portion of the depth collar to mesh with a second set of teeth alonga distal end portion of the ratcheting sleeve.

In a further embodiment, the step of moving the depth collar includes atleast partially aligning the one or more cutting surfaces and a viewingwindow along the depth collar relative to a longitudinal axis of thedrill shaft.

In a further embodiment, the method includes moving the drill shaftalong a guide pin situated at the surgical site.

In a further embodiment, the method includes moving the ratchetingsleeve away from the depth collar to cause a spring member to at leastpartially compress. The step of moving the ratcheting sleeve along thedrill shaft includes at least partially decompressing the spring memberto bias the ratcheting sleeve against the depth collar.

FIGS. 1-7 illustrate an exemplary cutting or drill assembly 20 that canbe utilized for various surgical procedures, such as for preparation ofa surgical site. For example, the assembly 20 may be utilized in ashoulder reconstruction to remove bone along an articulating surface ofa glenoid or humeral head. The bone may be removed adjacent to a defectin the articulating surface.

Referring to FIGS. 1-2, the assembly 20 includes an elongated drillshaft 22, a depth collar (or sleeve) 24, and a ratcheting sleeve 26. Thedrill shaft 22 can be utilized to form a recess in tissue along asurgical site, such as a bone hole. The depth collar 24 provides avariable depth feature and is dimensioned to set a depth of the hole orrecess formed in the surgical site. The ratcheting sleeve 26 cooperateswith the depth collar 24 to limit or otherwise oppose relative rotationor movement between the depth collar 24 and drill shaft 22.

The drill assembly 20 includes a depth ruler DR and a depth indicator DImoveable relative to each other to limit a depth of the hole or recessformed in the surgical site. In the illustrative embodiment of FIGS.1-2, the drill shaft 22 includes the depth indicator DI, and the depthcollar 24 includes the depth ruler DR. Of course, an oppositeconfiguration is also contemplated in which the drill shaft 22 includesthe depth ruler DR, and the depth collar 24 includes the depth indicatorDI. The depth indicator DI is aligned with a selected position along thedepth ruler DR in response to translating or otherwise moving the depthcollar 24 relative to the drill shaft 22.

The depth ruler DR can correspond to a range of depths of a hole orrecess to be formed in the surgical site. The depth ruler DR can rangebetween approximately 10 mm and approximately 36 mm in 1 mm incrementsas illustrated in FIGS. 1-2, for example. It should be appreciated thata minimum value of the depth ruler DR can be lesser or greater than 10mm, such as approximately 5 or 15 mm, and a maximum depth of the depthruler DR can be lesser or greater than 36 mm, such as approximately 30or 37 mm.

Referring to FIGS. 3-4, with continuing reference to FIG. 2, the drillshaft 22 extends along a longitudinal axis A, and includes a shankportion 28, an intermediate portion 30, and a drill body portion 32. Theshank portion 28 and drill body portion 32 include proximal and distalends of the drill shaft 22, respectively. The shank portion 28 can bedimensioned to cooperate with tooling T (shown in dashed lines in FIG. 2for illustrative purposes) to rotate or otherwise drive the shaft 22.For example, the shank portion 28 can be mounted to a chuck of thetooling T. The intermediate portion 30 extends along the longitudinalaxis A between the shank portion 28 and drill body portion 32. The drillbody portion 32 includes one or more cutting surfaces 34 spaced betweenone or more grooves or flutes 36. The depth indicator DI can be proximalto the drill body portion 32.

The assembly 20 includes at least one elongated viewing window 37 (FIGS.1-2) along a sidewall of the depth collar 24. The viewing window 37 isat least partially axially aligned with the cutting surfaces 34 anddepth indicator DI relative to the longitudinal axis A, as illustratedin FIG. 2.

The drill shaft 22 includes a first annular shoulder 38 that extendsabout an outer periphery 39 of the intermediate portion 30. Theintermediate portion 30 includes an elongated slot 40 dimensioned toextend along the longitudinal axis A between opposed sidewalls along theouter periphery 39 of the intermediate portion 30. The intermediateportion 30 includes a first threading 42 about the outer periphery 39.The first threading 42 is between the slot 40 and drill body portion 32.

Referring to FIG. 4, with continuing reference to FIGS. 2-3, the depthcollar 24 is disposed about the drill body portion 32 and is dimensionedto at least partially cover the cutting surface 34 for one or morepositions of the depth collar 24 relative to the longitudinal axis A.The depth collar 24 includes a main body 44 that extends between aproximal end portion 46 and a distal end portion 48 opposed to theproximal end portion 46. The distal end portion 48 is dimensioned tocontact tissue such as bone adjacent to the cutting surfaces 34, asillustrated in FIG. 10.

The depth collar 24 includes a first passageway 50 dimensioned to atleast partially receive the drill body portion 32 and intermediateportion 30 of the drill shaft 22. The depth collar 24 includes secondthreading 52 along the first passageway 50. The depth collar 24 ismoveable in a direction D1 towards a terminal end of the drill bodyportion 32, and is moveable in a direction D2 towards a terminal end ofthe shank portion 28 (see FIGS. 2 and 4). The first threading 42 alongthe drill shaft 22 is dimensioned to engage with the second threading 52such that relative rotation between the depth collar 24 and theintermediate portion 30 in a rotational direction R1 (e.g., clockwise orcounterclockwise) causes the depth collar 24 to translate or otherwisemove in the direction D1 or direction D2 along the longitudinal axis Aof the drill shaft 22. The depth collar 24 is moveable along the one ormore cutting surfaces 34 in response to relative rotation between thedepth collar 24 and the drill shaft 22. Relative movement between thedrill shaft 22 and depth collar 24 causes relative movement between thedepth indicator DI and depth ruler DR.

The drill shaft 22 can include a shaft passageway 41 extending along thelongitudinal axis A between the shank portion 28 and drill body portion32. The passageway 41 can be dimensioned to slidably receive a guide pinGP (shown in dashed lines for illustrative purposes). The passageway 41can be dimensioned such that the passageway 41 intersects the slot 40,as illustrated in FIG. 4.

Referring to FIGS. 4-5, with continuing reference to FIG. 2, theratcheting sleeve 26 includes a main body 56 that extends between aproximal end portion 58 and a distal end portion 60. The ratchetingsleeve 26 includes a second passageway 62 dimensioned to at leastpartially receive the intermediate portion 30 of the drill shaft 22. Theratcheting sleeve 26 includes a second annular shoulder 64 (FIG. 4)along the second passageway 62.

The assembly 20 includes a spring member 66 disposed along the outerperiphery 39 of the intermediate portion 30. The spring member 66 isdimensioned to bias the ratcheting sleeve 26 towards the depth collar 24in an installed position. The spring member 66 can be a coil spring asillustrated in FIGS. 4-5, for example. Other spring configurations canbe utilized, such as torsion springs and wave springs. The spring member66 is trapped between the first and second shoulders 38, 64 in theinstalled position, as illustrated in FIG. 4. The spring member 66 isdimensioned to bias the ratcheting sleeve 26 in the direction D1 towardsthe drill body portion 32. The spring member 66 is at least partiallycompressible between the first and second shoulders 38, 64 in responseto axially moving the ratcheting sleeve 26 in the direction D2 away fromthe drill body portion 32 and/or depth collar 24 relative to thelongitudinal axis A, as illustrated in FIG. 4 (see also FIG. 6).

The drill assembly 20 includes at least one fastener or retention pin 68mechanically attached to the ratcheting sleeve 26. Each retention pin 68is at least partially received in the slot 40. In the illustrativeembodiment of FIG. 4, the assembly 20 includes a pair of retention pins68 each extending inwardly from a sidewall of the ratcheting sleeve 26bounding the passageway 62. Each retention pin 68 is dimensioned tolimit relative rotation and axial movement between the ratcheting sleeve26 and drill shaft 22. The retention pins 68 are dimensioned totranslate or axially move relative to the longitudinal axis A in theslot 40 between opposed end faces 72, 74 (FIGS. 3-4) bounding the slot40.

In the illustrative embodiment of FIG. 4, the slot 40 extends betweenthe opposed sidewalls of the intermediate portion 30 such that the slot40 receives a pair of the retention pins 68. In other embodiments, thedrill shaft 22 includes separate and distinct slots 40 along the outerperiphery 39 of the intermediate portion 30 with the slots 40dimensioned to receive a respective retention pin 68.

The ratcheting sleeve 26 is moveable along the drill shaft 22 between afirst or fully retracted position (e.g., FIG. 6, with depth collar 24′shown in dashed lines for illustrative purposes), and a second,different position (e.g., FIG. 3, with collar 24″ and sleeve 26″ shownin dashed lines for illustrative purposes). FIGS. 2 and 4 illustrate theratcheting sleeve 26 in an intermediate position relative to thelongitudinal axis A of the drill shaft 22. The ratcheting sleeve 26 isspaced apart from the depth collar 24′ in the first position. Theratcheting sleeve 26 is engaged with the depth collar 24″ in the secondposition and can be engaged with the depth collar 24 in the intermediateposition such that the ratcheting sleeve 26 limits relative rotation andaxial movement between the depth collar 24, 24″ and drill shaft 22.

The retention pins 68 are dimensioned to abut against the first one ofthe end faces 72 in the first position and are dimensioned to abutagainst another one of the end faces 74 in the second position to limitaxial movement of the ratcheting sleeve 26 relative to the drill shaft22 (first and second positions indicated at 68′ and 68″ in dashed linesin FIG. 3 for illustrative purposes). FIG. 6 illustrates retention pin68′ with the ratcheting sleeve 26 moved in the direction D2 to the firstposition.

Each retention pin 68 is dimensioned to engage with lateral surfaces ofthe slot 40 to limit relative rotation between the ratcheting sleeve 26and drill shaft 22. The ratcheting sleeve 26 is disposed about theintermediate portion 30 of the drill shaft 22 such that the ratchetingsleeve 26 selectively limits relative rotation between the depth collar24 and drill shaft 22.

The assembly 20 includes an anti-rotation mechanism 75 (FIGS. 2 and 4)operable to limit relative rotation between drill shaft 22 and depthcollar 24. In the illustrated embodiment of FIGS. 2 and 4, theanti-rotation mechanism 75 includes a first set of teeth 76 dimensionedto engage and mesh with a second set of teeth 78. The depth collar 24can include the first set of teeth 76, and the ratcheting sleeve 26 caninclude the second set of teeth 78 (see also FIGS. 5-6). The first setof teeth 76 extend axially from the proximal end portion 46 of the depthcollar 24, and the second set of teeth 78 extend axially from the distalend portion 60 of the ratcheting sleeve 26 relative to the longitudinalaxis A. In the illustrated embodiment of FIG. 2, the first and secondsets of teeth 76, 78 have a generally sawtooth geometry. It should beappreciated that other geometries of the teeth 76, 78 can be utilized,such as a generally rectangular profile as illustrated by teeth 176, 178of FIG. 7.

The first set of teeth 76 are dimensioned to mate with the second set ofteeth 78 to oppose relative rotation between the depth collar 24 anddrill shaft 22. The spring member 66 is dimensioned to bias the secondset of teeth 78 in the direction D1 towards the first set of teeth 76.The second set of teeth 78 are dimensioned to mate with the first set ofteeth 76 in the position(s) in which the depth collar 24 abuts againstthe ratcheting sleeve 26, as illustrated in FIGS. 2-4. The teeth 76, 78can be disengaged by holding the depth collar 24 and rotating theratcheting sleeve 26 in a direction (e.g., clockwise orcounterclockwise) utilized to move the depth collar 24 away from thedrill body portion 32.

An exemplary method of use will now be described. Referring to FIG. 8,an exemplary method in a flowchart 80 for preparing a surgical site isshown. Reference is made to the drill assembly 20 of FIGS. 9-10 forillustrative purposes. In should be appreciated that one or more of thesteps of method 80 may be performed with the reaming assembly 20. Themethod 80 can be utilized to forming a recess or hole at a surgicalsite, such as a bone hole in an articulating surface of a glenoid. Thebone may be removed adjacent to a defect in the articulating surface.Fewer or additional steps than are recited below could be performedwithin the scope of this disclosure, and the recited order of steps isnot intended to limit this disclosure.

At step 80A, a position of the depth collar 24 is set corresponding to adepth of a recess or hole to be formed in a surgical site S (FIGS.9-10). Step 80A can include moving the depth collar 24 relative to thedrill shaft 22 such that the depth collar 24 at least partially coversone or more cutting surfaces 34 of the drill shaft 22. Step 80A includesat least partially aligning the cutting surfaces 34 and the viewingwindow 37 relative to the longitudinal axis A. The depth collar 24 ismoved to align the depth indicator DI with a selected value along thedepth ruler DR. Step 80A can include holding the drill shaft 22 androtating the depth collar 24 about the drill shaft 22 to cause therelative movement between the depth indicator DI and depth ruler DR. Thesurgeon can verify the position of the depth indicator DI through theviewing window 37. Step 80A can include, prior to moving the depthcollar 24 to a position corresponding to the selected depth, disengagingthe teeth 76, 78 and moving the ratcheting sleeve 26 away from the depthcollar 24 to cause the spring member 66 to at least partially compress,as illustrated in FIG. 6.

At step 80B, the ratcheting sleeve 26 is moved along the drill shaft 22to engage the depth collar 24 such that the ratcheting sleeve 26 limitsrelative rotation and axial movement between the depth collar 24 anddrill shaft 22. Step 80B can include moving the ratcheting sleeve 26along the drill shaft 22 to at least partially decompress the springmember 66 such that the spring member 66 biases the ratcheting sleeve 26against the depth collar 24, as illustrated in FIG. 4. Step 80B caninclude rotating the depth collar 24 and drill shaft 22 in therotational direction R1 relative to each other such that the threading42 along the drill shaft 22 engages the threading 52 along the depthcollar 24 to move the depth collar 24 along the longitudinal axis A, asillustrated in FIG. 4. Step 80B can include causing the teeth 76 alongthe depth collar 24 to mesh with the teeth 78 along the ratchetingsleeve 26, as illustrated in FIGS. 2 and 4.

Referring to FIG. 9, with continuing reference to FIG. 8, at step 80Cthe assembly 20 is positioned at the surgical site S. In embodiments,the surgical site S is a glenoid bone B of a shoulder joint. However,the method could be performed in various other tissue within the scopeof this disclosure. In other words, this disclosure is in no way limitedto forming a recess or hole in bone along the glenoid. Step 80C caninclude positioning the assembly 20 relative to a guide pin GP situatedin bone B at the surgical site S. The guide pin GP may be positioned atleast partially in the passageway 41 of the drive shaft 22, asillustrated in FIG. 4. Step 80C can include moving the drill shaft 22along the guide pin GP and into contact with the bone B.

Referring to FIG. 10, with continuing reference to FIG. 8, at step 80D aportion of the bone B or other tissue is removed at the surgical site Sto form a recess or bone hole BH dimensioned to the selected depthcorresponding to a position of the depth indicator DI relative to thedepth ruler DR. Step 80D can include rotating the drill shaft 22 in adirection R2 about the longitudinal axis A to form the bone hole BH. Theinstrument 20 can be removed from the surgical site S at step 80E.

Referring to FIG. 11, with continuing reference to FIG. 8, at step 80Fthe surgeon can position an implant such as a bone plate BP at thesurgical site S. Step 80F can include placing or otherwise securing agraft G to the bone plate BP. The graft G can have a generallywedge-shaped geometry as illustrated by FIGS. 11-12, for example. Thegraft G can be oriented relative to a defect in the bone B.

The bone plate BP can include an anchoring member BP-M. The anchoringmember BP-M can serve as a central post of the bone plate BP, forexample. The anchoring member BP-M can be positioned to extend throughan inner bore GB of the graft G to secure the bone plate BP at thesurgical site S. In other embodiments, the inner bore GB is omitted. Thegraft G is dimensioned to extend along a backside of the bone plate BPsuch that at least a portion of the graft G is spaced apart from asidewall of the bone plate BP, as illustrated in FIG. 11.

The surgical site S may be prepared for receiving the graft G and atleast a portion of the bone plate BP. This may include forming at leastone recess BR in the bone B. The recess BR may be formed to removetissue from a defect in the bone B. The recess BR can be dimensioned toat least partially receive the bone plate BP and graft G. The recess BRmay be drilled, punched, reamed, tapped, or otherwise formed. The boneplate BP can be situated at the surgical site S such that the backsideof the bone plate BP abuts against surfaces of the recess BR.

The bone hole BH is dimensioned to extend inwardly from a floor of therecess BR, as illustrated in FIG. 11. The bone hole BH is dimensioned toat least partially receive the anchoring member BP-M. The anchoringmember BP-M can be screwed or press fit into the bone hole BH, forexample, to secure the bone plate BP.

A head portion or glenosphere HP can be secured to the bone plate BP toprovide an articulating surface for mating with an opposed articulatingmember M. The articulating member M can be an implant secured to thehumerus, for example. In other embodiments, the bone plate BP providesthe articulating surface.

The novel device and method of this disclosure provide versatility inpreparing a surgical site. The disclosed drill assembly 20 can beutilized to form a bone hole or recess having various depths anddimensions. The drill assembly 20 includes one or more features thatlimit relative rotation and/or axial movement between the drill shaft 22and depth collar 24, which can improve precision in setting andmaintaining the selected depth of the bone hole or recess to be formedin the surgical site.

Although the different non-limiting embodiments are illustrated ashaving specific components or steps, the embodiments of this disclosureare not limited to those particular combinations. It is possible to usesome of the components or features from any of the non-limitingembodiments in combination with features or components from any of theother non-limiting embodiments.

It should be understood that like reference numerals identifycorresponding or similar elements throughout the several drawings. Itshould further be understood that although a particular componentarrangement is disclosed and illustrated in these exemplary embodiments,other arrangements could also benefit from the teachings of thisdisclosure.

The foregoing description shall be interpreted as illustrative and notin any limiting sense. A worker of ordinary skill in the art wouldunderstand that certain modifications could come within the scope ofthis disclosure. For these reasons, the following claims should bestudied to determine the true scope and content of this disclosure.

What is claimed is:
 1. A drill assembly for preparation of a surgicalsite, comprising: a drill shaft including one or more cutting surfaces;a depth collar dimensioned to at least partially cover the one or morecutting surfaces, and the depth collar including a first set of teeth; aratcheting sleeve including a second set of teeth, the second set ofteeth dimensioned to mate with the first set of teeth to oppose relativerotation between the depth collar and the drill shaft; and wherein, whenthe first set of teeth and the second set of teeth are engaged together,the ratcheting sleeve limits movement of the depth collar.
 2. Theassembly as recited in claim 1, wherein: the drill shaft includes anintermediate portion between a shank portion and a drill body portion,the drill body portion comprising the one or more cutting surfaces; thedepth collar includes first threading along a first passagewaydimensioned to at least partially receive the intermediate portion; andthe intermediate portion includes second threading dimensioned to engagewith the first threading such that relative rotation between the depthcollar and the intermediate portion causes the depth collar to movealong a longitudinal axis of the drill shaft.
 3. The assembly as recitedin claim 2, wherein the first set of teeth extend axially from aproximal end portion of the depth collar relative to the longitudinalaxis, and the second set of teeth extend axially from a distal endportion of the ratcheting sleeve relative to the longitudinal axis. 4.The assembly as recited in claim 2, further comprising: a spring memberthat biases the second set of teeth towards the first set of teeth. 5.The assembly as recited in claim 2, wherein the depth collar includes aviewing window at least partially axially aligned with the one or morecutting surfaces relative to the longitudinal axis.
 6. The assembly asrecited in claim 1, further comprising: a spring member that biases theratcheting sleeve towards the depth collar in an installed position. 7.The assembly as recited in claim 6, wherein: the drill shaft includes anintermediate portion between a shank portion and a drill body portion,the drill body portion comprising the one or more cutting surfaces; theintermediate portion includes a first shoulder; the ratcheting sleeveincludes a second passageway at least partially receiving theintermediate portion, and the ratchet sleeve includes a second shoulderalong the second passageway; and the spring member is compressiblebetween the first shoulder and the second shoulder in response to movingthe ratcheting sleeve in a direction away from the drill body portion.8. The assembly as recited in claim 7, wherein the intermediate portionincludes a slot, and further comprising: a retention pin mechanicallyattached to the ratcheting sleeve such that the retention pin is atleast partially received in the slot.
 9. The assembly as recited inclaim 8, wherein the retention pin extends inwardly from a sidewall ofthe ratcheting sleeve bounding the second passageway such that theretention pin limits relative rotation between the ratcheting sleeve andthe drill shaft.
 10. The assembly as recited in claim 9, wherein thedrill shaft includes a shaft passageway extending along a longitudinalaxis between the shank portion and the drill body portion such that theshaft passageway intersects the slot.
 11. A drill assembly forpreparation of a surgical site, comprising: a drill shaft including oneor more cutting surfaces; a depth collar movable along the one or morecutting surfaces in response to relative rotation between the depthcollar and the drill shaft, wherein the depth collar includes a distalend portion dimensioned to contact bone adjacent to the one or morecutting surfaces; and a ratcheting sleeve moveable along the drill shaftbetween a first position and a second, different position relative to alongitudinal axis of the drill shaft, wherein the ratcheting sleeve isspaced apart from the depth collar in the first position and is engagedwith the depth collar in the second position such that the ratchetingsleeve limits relative rotation between the depth collar and the drillshaft.
 12. The assembly as recited in claim 11, wherein: the depthcollar includes a first set of teeth; and the ratcheting sleeve includesa second set of teeth dimensioned to mate with the first set of teeth inthe second position.
 13. The assembly as recited in claim 11, furthercomprising a retention pin that limits relative rotation between theratcheting sleeve and the drill shaft.